Ghrelin is the endogenous ligand for the growth hormone (GH) secretagogue receptor. It was originally purified from stomach and is a 28 amino acid peptide hormone in which the serine at position 3 is n-octanoylated. It has potent GH releasing activity and thus is believed to play an important role in maintaining GH release and energy homeostasis (Non-patent literature, NPL 1). In particular, it appears to exert potent appetite-stimulating activities. Then it has been known that a ghrelin agonist is useful for the treatment and/or prophylaxis of cancer anorexia/cachexia (NPL 2, 3 and 4); cachexia and anorexia by anti-cancer drugs (NPL 4 and 5); hyperalgesia by anti-cancer drugs (NPL 5); COPD/COPD cachexia (NPL 6 and 7); sarcopenia (NPL 8); eating disorders and neurological eating disorders (NPL 9); weight loss suppression (NPL 10); early postoperative recovery of cancer patients (NPL 11); chronic respiratory tract infection (NPL 7); inflammation (NPL 12); IBD (NPL 12); FD (NPL 4); constipation (NPL 9); diabetic gastroparesis and gastroparesis (NPL 4 and 13); heart failure (NPL 14, 15 and 16); myocardial infarction (NPL 14, 15 and 16); diabetic neuropathy (NPL 17); Parkinson's disease (NPL 18); multiple sclerosis (NPL 19); diagnosis and treatment of growth hormone deficiency (NPL 20); elderly QOL improvement (NPL 20); bowel movement disturbance of spinal cord injury patients (NPL 21); postoperative ileus (NPL 4 and 22); and morphine induced ileus (NPL 22).